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Ontario Running Weather

Friday, April 17, 2026 · Hour-by-hour forecast updated 6:08 AM PDT

Best Time to Run in Ontario Today

5 AM–12 PM

64°F and clear at peak. Wind 4 mph from the W, dew point 50°F.

99
Peak FitScore
Temperature
64°F / feels 63°
Wind
4 mph W, gusts 5
Dew Point
50°F — comfortable
Humidity
60%
UV Index
4 — Moderate
Air Quality
59 AQI — Moderate

Hourly running conditions

🌅 6 AM
90
52° feels 49° 5 mph NW
☀️ 7 AM
93
53° feels 51° 3 mph WNW 1% rain
🌤️ 8 AM
98
57° feels 55° 4 mph W 1% rain
☀️ 9 AM
98
60° feels 58° 3 mph W
☀️ 10 AM
99
64° feels 63° 4 mph W
☀️ 11 AM
92
68° feels 69° 4 mph W
☀️ 12 PM
84
73° feels 74° 4 mph WNW
☀️ 1 PM
79
76° feels 77° 4 mph WNW
☀️ 2 PM
78
78° feels 78° 5 mph WNW
🌤️ 3 PM
79
79° feels 77° 5 mph WNW
☀️ 4 PM
81
80° feels 76° 5 mph W
☀️ 5 PM
84
79° feels 73° 8 mph W
80–100 Excellent 60–79 Good 40–59 Fair Below 40 Poor

7-day running forecast

Today Apr 17
80° / 52°
99
🏃 All day
☁️
Sat Apr 18
86° / 52°
99
🏃 All day
☁️
Sun Apr 19
81° / 64°
90
🏃 9 AM–12 PM
☁️
Mon Apr 20
79° / 60°
94
🏃 9 AM–12 PM
🌧️
Tue Apr 21
75° / 59°
89
🏃 9 AM–12 PM
🌧️
Wed Apr 22
68° / 57°
95
🏃 9 AM–12 PM
🌤️
Thu Apr 23
70° / 54°
99
🏃 9 AM–12 PM
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Running Forecast
iMessage
🌤 Tomorrow in Ontario: Best window: 9–11 AM (FitScore 95) 6am: 48°F, feels 45° — NW 8mph 9am: 58°F, feels 56° — W 12mph 12pm: 66°F, feels 65° — SW 8mph ☔ Rain likely after 3pm.
Yesterday 8:14 PM Nightly

Ontario running weather FAQ

What's the best time to run in Ontario today?

Based on today's FitScore analysis, the best time to run is 5 AM–12 PM with a peak FitScore of 99/100. Check the hourly breakdown above for detailed conditions throughout the day.

What months are best for running in Ontario?

The best months for running in Ontario are June, July, August, September. The most challenging months are typically November, December. Mild summers with low humidity make for ideal running. Watch for marine layer fog in coastal areas.

What is the FitScore?

FitScore rates each hour from 0–100 for outdoor exercise based on temperature, humidity, dew point, wind, precipitation probability, UV index, and air quality. Higher scores mean better conditions.

Nearby:Pomona, CAFontana, CACorona, CA
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